Answer:
8m/s
Explanation:
i think i had this question on a test i'm taking so i'm assuming i cannot say for sure if this is correct
(I assume that the 4 directions north-south-east-west are meant with respect to the wire seen from the top.)
We can use the right-hand rule to understand the direction of the magnetic field generated by the wire. The thumb follows the direction of the current in the wire (upward), while the other fingers give the direction of the field in every point around the wire. Seen from the top, the field has an anti-clockwise direction. Therefore, if we take a point at east with respect to the wire, in this point the field has direction south.
Answer:
the tension in each side of the cable is 3677.57 N
Explanation:
given data
traffic light = 20 kg
cable between two poles = 30 m
sag in the cable = 0.40 m
solution
by the free body diagram
tan θ = 
.............1
θ = 1.527 °
and
tension = mg
The net force is along x - axis is express as
T2 cosθ = T1 cosθ .................2
so T2 - T1 ..............3
and
when we take it along y axis that is express as
( T1 + T2) sinθ = mg ...................4
so by equation 3 we put here
2 × T1 sin(1.527) = 20 × 9.8
T1 = 3677.57 N
Answer:
12.5 ft/s
Explanation:
Height of person = 6 ft
height of lamp post = 10 ft
According to the question,
dx / dt = 5 ft/s
Let the rate of tip of the shadow moves away is dy/dt.
According to the diagram
10 / y = 6 / (y - x)
10 y - 10 x = 6 y
y = 2.5 x
Differentiate both sides with respect to t.
dy / dt = 2.5 dx / dt
dy / dt = 2.5 (5) = 12.5 ft /s
I have three problems with this question.
#1). If you copied the question exactly the way it's written,
then the question is written very badly. The wording is
misleading, and the more you try to think about it and
puzzle it out, the more it'll damage your understanding
of Physics.
There is no relationship between the force exerted on an
elevator and the distance the elevator is lifted.
-- If the force is anything more than the weight of the elevator ...
even one ounce more ... then it'll lift the elevator as high as
you want.
-- If the force is anything less than the weight of the elevator ...
even one ounce less, then that elevator is headed for the bottom.
#2). You didn't post any graph below, so if we need the graph
to answer the question, then we can't answer the question.
#3). I guess that's OK, because you didn't ask any question.
